Jáchymovite

 IMA-A 1994-025
Uranium 31.2.6.2
(Dana Classification Number)
(No Images) 6/D.20-05
(Strunz ID)

Property Data Remarks
Named for: Jáchymov (St Joachimsthal), Krusné Hory (Erzgebirge), Západoceský Kraj, Bohemia, Czech Republic, its type location
Alternate
    Name(s):
  		•  
    Mineral Class:
    Sulfates,Chromates,Molybdates and Tungstates
      Uranylsulfates [UO2]+2 - [SO4]-2
        Uranopilite - Rabejacite series
    		 
    Chemical
        Formula:    		 (UO2)8(SO4)(OH)14 · 13H2O  
    Chemical
        Composition:
    Hydrogen: (H) 1.48%
    Oxygen: (O) 27.56%
    Sufur: (S) 1.18%
    Uranium: (U) 69.79%
    		by weight
    Molecular
        Weight:    		 2,728.59 daltons (amu)
    Specific
        Radioactivity:

    (All radiation is for a 1 gram, fully aged specimen)

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    1.24921 × 1005 3.38 × 10-06 1.67 167.43

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Monoclinic
    Axial Ratios: a: 2.0001
    b: 1
    c: 1.4588
    Cell Dimensions: a: 18.553 Å
    b: 9.276 Å
    c: 13.532 Å
    Z: 2
    b: 125.56°
    V: 1,894.52 Å3
    DenCalc: 4.78
    H-M Symbol:  
    Space Group: P21, P21/m
    X-Ray Diffraction:
      By Intensity ( I/Io )    		 (1): 7.56 Å
    (0.48): 7.13 Å
    (0.34): 3.771 Å
    		 
    Habit:
  • Acicular
    		•   
    Cleavage:
    [001]  
    [010] Perfect
    [100]  
    		 
    Fracture: Brittle  
    Moh's
        Hardness:    		    
    Density: 4.79 grams/cm3
    Color: Yellow  
    Streak: Pale yellow  
    Luster: Vitreous  
    Diaphaneity: Translucent  
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:  
    Short Wave:  
    		 
    Magnetism: Non-magnetic  
    Occurance:
  • Found in a dolomite-vein
    		•   
    Associated
        Minerals:

    Albrechtschraufite, Andersonite, Antimony, Aragonite, Argentopyrite, Arsenic, Arsenopyrite, Arsenuranospathite, Autunite, Barite, Becquerelite, Bismuth, Bornite, Calcite, 'Chlorite', Chrysocolla, Cinnabar, Cobaltite, Coffinite, Compreignacite, Copper, Cuprite, Cuprosklodowskite, Curienite, Dewindtite, Dolomite, Fluorite, Galena, Gold, Graphite, Gypsum var: Selenite, Hematite, 'Hydronium Uranospinite', Johannite, Kahlerite, Kamotoite-(Y), Kaolinite, Kasolite, Liebigite, 'Limonite', Magnesium-Zippeite, Magnetite, Malachite, Manganite, Masuyite, Meta-Autunite, Meta-Uranopilite, 'Meta-Uranospinite', Metalodevite, Metanovácekite, Metaschoepite, Metatorbernite, Metatyuyamunite, Metazellerite, Metazeunerite, Molybdenite, Muscovite, Nickel-Zippeite, Nickeline, Novácekite, 'Olivine', Opal, Parsonsite, Phosphuranylite, Pyrargyrite, Pyrite, Pyrrhotite, Quartz, Rabbittite, Rabejacite, Realgar, Rhodochrosite, Richetite, Rutile, Schoepite, Schröckingerite, 'Serpentine Group', Silver, Sklodowskite, Skutterudite, Smithsonite, Soddyite, Sodium-Zippeite, Stibnite, Sulphur, Talc, Tenorite, Tetrahedrite, Titanite, Topaz, Torbernite, 'Tourmaline Group', Trögerite, Tyuyamunite, Urancalcarite, Uraninite, Uranocircite, Uranophane, Uranophane-beta, Uranopilite, Uranospathite, Uranosphaerite, Uranospinite, Vandendriesscheite, Voglite, Walpurgite, Weeksite, 'Wolframite', Wolsendorfite, Wulfenite, Xenotime-(Y), Yingjiangite, Zellerite, Zeunerite, Zippeite, Znucalite

    Minerals   -   Uranium & Thorium
    mineral links

    		These are a few of the minerals known to be found with Jáchymovite
    Localities:

    Extremely rare

    Jachymovite Localities
    Notes:

    Strongly radioactive a- and b-particles, g-rays.

    Crystals are probably metamic.